package com.gupaoedu.vip.pattern.springmvc2.webmvc.servlet;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.RandomAccessFile;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class MyView {

    public static final String DEFAULT_CONTENT_TYPE ="text/html;charset=utf-8";


    private File viewFile;

    public MyView(File viewFile) {
        this.viewFile = viewFile;
    }

    public void render(Map<String, ?> model, HttpServletRequest request, HttpServletResponse response) throws Exception {
        StringBuffer sb = new StringBuffer();
        RandomAccessFile ra = new RandomAccessFile(this.viewFile, "r");
        String line = null;
        while(null!=(line=ra.readLine())){
            line = new String(line.getBytes("ISO-8859-1"), "utf-8");
            Pattern pattern = Pattern.compile("￥\\{[^\\}]+\\}",Pattern.CASE_INSENSITIVE);
            Matcher matcher = pattern.matcher(line);
            while(matcher.find()){
                String paramName = matcher.group().replaceAll("￥\\{|\\}","");
                Object paramValue = model.get(paramName);
                if(null == paramValue){continue;}
                line = matcher.replaceFirst(paramValue.toString());
                matcher = pattern.matcher(line);
            }
            sb.append(line);
        }
        response.setCharacterEncoding("utf-8");
        response.getWriter().write(sb.toString());
    }
}
